Is Benadryl Safe for Dogs?

on September 21, 2022

Is Benadryl Safe for Dogs? 

Just like humans, dogs get insect bites, allergies, hives, itchy skin and other allergic reactions. You may want to reach for the Benadryl for your pet. Or maybe a well-meaning friend has told you to use Benadryl for your dog to make them sleepy and combat motion sickness before traveling.

Before you go dosing your fur baby with the pink stuff, read about the do’s and don'ts of Benadryl for dogs.

Also note: this is not medical advice. Talk to your vet before giving your dog a new food, supplement or medication (especially a medication). Read about side effects of Benadryl in this article below.

What is Benadryl?

Benadryl is a brand name for an antihistamine medication, diphenhydramine HCL. If you’ve heard the term “antihistamine” before, it's because they’re common anti-allergy drugs. 

Histamines are natural, immune system chemicals. In the event of an allergic response, histamines flare up and cause itching, inflammation, sneezing, maybe even breathing problems. 

So you might be asking, “Why would the body do that!?” 

To the body, a human body or a dog body alike, allergens are treated like a toxin or a poison. So those responses are actually an attempt to get rid of a toxin, through the skin or breathing. Essentially, histamines expel foreign invaders in the body. But their tactics cause some unwanted symptoms, like itching and sneezing. 

So how does an antihistamine work?

When you want to stop an allergic response, you block the histamines. Medications like Benadryl do this by crossing the blood brain barrier and blocking the signal for the immune response at its source. 

Can I Use Human Benadryl for Dogs?

In general, do not use human medications for pets. These often contain other ingredients like decongestants, alcohols, artificial sweeteners, or formulas which can lead to an overdose (like liquid or time-release formulas).

In a pinch, pure human Benadryl is generally considered safe for dogs, so long as it does not contain any other ingredients than the diphenhydramine HCL. It must also be administered in the correct dosage, which might include cutting a pill and measuring milligrams.

For these reasons, it’s best to get veterinary permission before administering human Benadryl to pets.

When Do You Use Benadryl for Dogs?

So you’ve worked out the dosage and the right ingredients to give your dog Benadryl. What does Benadryl do?

Benadryl is best used for:

  • Immediate allergic response, such as an insect sting. Swelling, itching and inflammation from an insect sting can be serious or even fatal. In these cases, quickly administering the correct dosage of Benadryl can be life-saving. 
  • Mild to moderate allergy symptoms are often treated with antihistamines, including Benadryl. Allergy symptoms include hives (red, itchy bumps), swelling and inflammation, runny eyes and nose and sneezing.

So what about treating your dog’s anxiety (such as travel anxiety) with Benadryl? Remember that advice from a well-meaning friend?

It is true that Benadryl may make your dog relaxed and sleepy, which sounds useful for travel, fireworks, thunderstorms, or other situational anxiety. However, some dogs have the opposite reaction and get more anxious or hyper. So, check with a vet before using Benadryl for anxiety.

See below for some alternatives to Benadryl for dogs, such as natural treatments for anxiety.

What are the Side Effects of Benadryl for Dogs?

All medications have intended effects and unintended effects, known as side effects. The same is true for our dogs! 

While Benadryl is generally well-tolerated when used correctly, it does cross the blood brain barrier, have potential side effects and also poses additional safety risks for dogs with certain health conditions. 

Side effects of Benadryl include:

  • Drowsiness, 
  • Dry eyes, dry mouth, nose, or throat,
  • Hyper-salivation (extra drooling)
  • Decreased urination or constipation, 
  • Diarrhea, vomiting or upset stomach,
  • Restlessness, anxiety or hyperactivity,
  • Possible allergic reaction including: hives, difficulty breathing, swelling of the face, lips, tongue, or throat, and/or an increased heart rate. 

In the event of an allergic reaction to Benadryl, seek emergency veterinary care.

Dogs with the following health conditions should not use Benadryl unless directed by a veterinary professional:

  • Low blood pressure
  • Cardiac (heart) conditions
  • Glaucoma (an eye condition)

When in doubt, reach out! Ask your vet before giving any medication.

Are There Alternatives to Benadryl for Dogs?

It may be possible to treat the same symptoms that get you reaching for the Benadryl, with safer, alternative methods.

  • In the event of an insect sting: use a card (such as a credit card) to scrape and remove a stinger. Do not use tweezers, since squeezing a little stinger can release more venom. Make a compress of baking soda with a little water and apply it to the affected area. A soothing oatmeal bath can also help!
  • For mild to moderate allergy symptoms: Our Oatmeal Anti-itch CBD Shampoo is specially formulated to soothe itchy skin. Consider also boosting the immune system with Probiotic Gut Health CBD Treats.
  • For doggy anxiety: Got an anxious pet? Treat situational and chronic anxiety both with calming CBD for dogs.

Not sure where to begin?

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